Method for adsorption of fluid contaminants and regeneration of the adsorbent

Abstract

The invention provides methods for treating a fluid, particularly water, contaminated with organic compounds, organisms, toxic substances, hazardous substances, ammonia, or mixtures thereof, by adsorption with an adsorbent material and regeneration of the purified adsorbent material. The contaminants may be first adsorbed onto the adsorbent material, which is then regenerated by treatment with nanoparticles of at least one transition metal oxide catalyst and at least one oxidant; or the contaminants are adsorbed onto particles of the adsorbent material loaded with at least one transition metal oxide, which is then regenerated by treatment with an oxidant; or the contaminated fluid is treated with an oxidant first and then with particles of the adsorbent material loaded with at least one transition metal oxide. The adsorbed contaminants are converted into environmentally compatible products.

1 . A method for treating a fluid containing contaminants selected from the group consisting of organic compounds, organisms, toxic substances, hazardous substances, ammonia, or mixtures thereof, by adsorption with an adsorbent material and regeneration of the purified adsorbent material, said method comprising:
 a) adsorption of said contaminants onto particles of an adsorbent material selected from the group consisting of activated carbon, activated alumina, activated TiO 2 , mineral clay, zeolite, an ion exchanger, or mixtures thereof; and   b) regeneration of the adsorbent material by contact with nanoparticles of at least one transition metal oxide catalyst and at least one oxidant, whereby the adsorbed contaminants are converted into environmentally compatible products.   
     
     
         2 . The method according to  claim 1 , wherein steps a) and b) occur concomitantly. 
     
     
         3 . A method for treating a fluid containing contaminants selected from the group consisting of organic compounds, organisms, toxic substances, hazardous substances, ammonia, or mixtures thereof, by adsorption with an adsorbent material and regeneration of the purified adsorbent material, said method comprising:
 a) adsorption of said contaminants on particles of an adsorbent material selected from the group consisting of activated carbon, activated alumina, activated TiO 2 , mineral clay, zeolite, an ion exchanger, or mixtures thereof, loaded with nanoparticles of at least one transition metal oxide catalyst; and   b) regeneration of the adsorbent material by contact with at least one oxidant, whereby the adsorbed contaminants are converted into environmentally compatible products.   
     
     
         4 . A method for treating a fluid containing contaminants selected from the group consisting of organic compounds, organisms, toxic substances, hazardous substances, ammonia, or mixtures thereof, by adsorption with an adsorbent material and regeneration of the purified adsorbent material, said method comprising:
 a) loading an adsorbent material selected from the group consisting of activated carbon, activated alumina, activated TiO 2 , mineral clay, zeolite, an ion exchanger, or mixtures thereof, with nanoparticles of at least one transition metal oxide catalyst;   b) treating the contaminated fluid with at least one oxidant; and   c) mixing with, or passing through, the contaminated fluid containing the oxidant of b) through the loaded adsorbent material of a), whereby the adsorbed contaminants are converted into environmentally compatible products, thus obtaining purified adsorbent material.   
     
     
         5 . The method according to  claim 1 , wherein the adsorbent material is virgin or regenerated activated carbon. 
     
     
         6 . The method according to  claim 3 , wherein the adsorbent material is virgin or regenerated activated carbon. 
     
     
         7 . The method according to  claim 4 , wherein the adsorbent material is virgin or regenerated activated carbon. 
     
     
         8 . (canceled) 
     
     
         9 . The method according to  claim 1 , wherein the transition metal oxide catalyst is an iron oxide, TiO 2 , or a mixture thereof, the iron oxide is selected from the group consisting of Fe 2 O 3 , FeOOH, FeFe 2 O 3 , MnFe 2 O 3 , CoFe 2 O 3 , CuFe 2 O 3 , and a mixture thereof., and the oxidant is selected from the group consisting of oxygen, ozone, hydrogen peroxide, hydroxyl radicals, inorganic ions radicals, oxone, and mixtures thereof. 
     
     
         10 . The method according to  claim 3 , wherein the transition metal oxide catalyst is an iron oxide, TiO 2 , or a mixture thereof, the iron oxide is selected from the group consisting of Fe 2 O 3 , FeOOH, FeFe 2 O 3 , MnFe 2 O 3 , CoFe 2 O 3 , CuFe 2 O 3 , or a mixture thereof, and the oxidant is selected from the group consisting of oxygen, ozone, hydrogen peroxide, hydroxyl radicals, inorganic ions radicals, oxone, and mixtures thereof. 
     
     
         11 . The method according to  claim 4 , wherein the transition metal oxide catalyst is an iron oxide, TiO 2 , or a mixture thereof, the iron oxide is selected from the group consisting of Fe 2 O 3 , FeOOH, FeFe 2 O 3 , MnFe 2 O 3 , CoFe 2 O 3 , CuFe 2 O 3 , or a mixture thereof, and the oxidant is selected oxygen, ozone, hydrogen peroxide, hydroxyl radicals, inorganic ions radicals, oxone, or mixtures thereof. 
     
     
         12 . The method according to  claim 1 , wherein the treated fluid is liquid and said liquid is potable water, ground water, or industrial, agricultural or municipal wastewater. 
     
     
         13 . The method according to  claim 3 , wherein the treated fluid is a liquid and said liquid is potable water, ground water, or industrial, agricultural or municipal wastewater. 
     
     
         14 . The method according to  claim 4 , wherein the treated fluid is a liquid and said liquid is potable water, ground water, or industrial, agricultural or municipal wastewater. 
     
     
         15 . The method according to  claim 1  for purification of water by adsorption with an adsorbent material and concomitant regeneration of the purified adsorbent material, comprising the following steps:
 a) purifying the water by adsorption of water contaminants selected from the group consisting of organic compounds, organisms, toxic substances, hazardous substances, ammonia, and of mixtures thereof, on an adsorbent material selected from the group consisting of activated carbon, activated alumina, activated TiO 2 , mineral clay, zeolite, an ion exchanger, or mixtures thereof; and   b) mixing with, or passing through, the adsorbent material containing the contaminants a solution comprising nanoparticles of at least one transition metal oxide selected from the group consisting of Fe 2 O 3 , FeOOH, FeFe 2 O 3 , MnFe 2 O 3 , CoFe 2 O 3 , CuFe 2 O 3 , TiO 2 , and of mixtures thereof, and at least one oxidant selected from the group consisting of oxygen, ozone, hydrogen peroxide, hydroxyl radicals, inorganic ions radicals, oxone, and mixtures thereof, to yield a purified adsorbent material and environmentally compatible reaction products.   
     
     
         16 . The method according to  claim 4  for purification of water by adsorption with an adsorbent material and concomitant regeneration of the purified adsorbent material, comprising the following steps:
 a) loading an adsorbent material selected from the group consisting of activated carbon, activated alumina, activated TiO 2 , mineral clay, zeolite, an ion exchanger, and mixtures thereof, with at least one transition metal oxide nanocatalyst selected from the group consisting of Fe 2 O 3 , FeOOH, FeFe 2 O 3 , MnFe 2 O 3 , CoFe 2 O 3 , CuFe 2 O 3 , TiO 2 , and mixtures thereof;   b) purifying the water by adsorption of water contaminants selected from the group consisting of organic compounds, organisms, toxic substances, hazardous substances, ammonia, and mixtures thereof, on said loaded adsorbent material of a); and c) mixing with, or passing through, the loaded adsorbent material containing the adsorbed contaminants produced in step b), a solution comprising at least one oxidant selected from the group consisting of oxygen, ozone, hydrogen peroxide, hydroxyl radicals, inorganic ions radicals, oxone, and mixtures thereof, to yield a purified adsorbent material and environmentally compatible reaction products.   
     
     
         17 . The method according to  claim 3  for purification of water by adsorption with an adsorbent material and concomitant regeneration of the purified adsorbent material, comprising the following steps:
 a) loading an adsorbent material selected from the group consisting of activated carbon, activated alumina, activated TiO 2 , mineral clay, zeolite, an ion exchanger, and mixtures thereof, with at least one transition metal oxide nanocatalyst selected from the group consisting of Fe 2 O 3 , FeOOH, FeFe 2 O 3 , MnFe 2 O 3 , CoFe 2 O 3 , CuFe 2 O 3 , TiO 2 , or mixtures thereof; b) adding to polluted water at least one oxidant selected from the group consisting of oxygen, ozone, hydrogen peroxide, hydroxyl radicals, inorganic ions radicals, oxone, and mixtures thereof; and   c) mixing and/or passing the polluted water of b) containing the oxidant through said loaded adsorbent material of a), to yield purified water, purified adsorbent material and environmentally compatible reaction products.   
     
     
         18 . The method according to  claim 1 , wherein said environmentally compatible reaction products comprise CO 2 , H 2 O and mineral acids. 
     
     
         19 . The method according to  claim 3 , wherein said environmentally compatible reaction products comprise CO 2 , H 2 O and mineral acids. 
     
     
         20 . (canceled) 
     
     
         21 . (canceled) 
     
     
         22 . The method according to  claim 1   4 , wherein the fluid is obtained from contaminated sludge or other solid waste mixed with or adsorbed by soil, by extracting the sludge, soil waste, or soil with an organic solvent or with water containing one or more detergents to produce a fluid containing the hazardous organic materials. 
     
     
         23 . A method of regeneration of spent adsorbent material containing adsorbed contaminants selected from organic compounds, organisms, toxic substances, hazardous substances, ammonia, or mixtures thereof, by mixing the spent adsorbent material with a solution comprising at least one oxide of transition metal nano-catalyst and at least one oxidant, to yield an adsorbent material substantially free from said adsorbed contaminants. 
     
     
         24 . The method according to  claim 23 , wherein said adsorbent material is selected from the group consisting of activated carbon, activated alumina, activated titanium dioxide, mineral clay, zeolite, ion exchangers, and mixtures thereof. 
     
     
         25 . The method according to  claim 23 , wherein said at least one oxide of transition metal is an iron oxide, TiO 2 , or a mixture thereof, said iron oxide is selected from the group consisting of Fe 2 O 3 , FeOOH, FeFe 2 O 3 , MnFe 2 O 3 , CoFe 2 O 3 , CuFe 2 O 3 , and a mixture thereof, and said oxidant is selected from the group consisting of oxygen, ozone, hydrogen peroxide, hydroxyl radicals, inorganic ions radicals, oxone, and mixtures thereof. 
     
     
         26 . (canceled) 
     
     
         27 . (canceled) 
     
     
         28 . The method according to  claim 23 , wherein the adsorbent material is virgin or regenerated activated carbon, the at least one transition metal oxide nanocatalyst is an iron (III) oxide, and the at least one oxidant is hydrogen peroxide. 
     
     
         29 . The method according to  claim 4 , wherein said environmentally compatible reaction products comprise CO 2 , H 2 O and mineral acids. 
     
     
         30 . The method according to  claim 3 , wherein the fluid is obtained from contaminated sludge or other solid waste mixed with or adsorbed by soil, by extracting the sludge, soil waste, or soil with an organic solvent or with water containing one or more detergents to produce a fluid containing the hazardous organic materials. 
     
     
         31 . The method according to  claim 4 , wherein the fluid is obtained from contaminated sludge or other solid waste mixed with or adsorbed by soil, by extracting the sludge, soil waste, or soil with an organic solvent or with water containing one or more detergents to produce a fluid containing the hazardous organic materials.